OLDPPositionMap.prototype.addMap = function (){
	// map layer
	var hel = new OpenLayers.Layer.WMS(
		"Opaskartta"
		,"components/com_dpposition/map.php"
		,{layers: 'Opaskartta'}
		,{
			buffer: 0
			,units:         "m"
			,tileSize:      new OpenLayers.Size(256, 256)
			,maxExtent:     new OpenLayers.Bounds(42600, 10400, 65310, 32000)
			,maxResolution: 2
			,minResolution: 8
			,numZoomLevels: 3
			,attribution: '&copy; Kaupunkimittausosasto, Helsinki 593/2008'
		}
	);
	this.map.addLayer(hel);
	this.mapType = OLDPPositionMap.MAP_TYPE_HEL;
	
	// show attribution
	this.map.addControl(new OpenLayers.Control.Attribution());
	
	// icon layer
	this.markers  = new OpenLayers.Layer.Markers( "Markers", {
		maxExtent: this.map.getMaxExtent()
		,maxResolution: 2
		,minResolution: 8
		,numZoomLevels: 3
	});
	this.map.addLayer(this.markers);
};